I've reluctantly hung up a trap (strategically placed as to not attract them from the entire neighborhood). It is amazing how many are in that thing after just one day. But I'm still battling them and trying to keep them off my roses, cannas, even marigolds.

Do they ever go away or are they here for the rest of the summer?

I understand that you need to go after the grubs with insecticide but don't like doing that because it is risky for the birds in my yard. Does anyone know how Olbrich deals with them or have any ideas of your own?

I have researched (Googled) the Japanese Beetle plague. The traps are of limited effectiveness as they apparently bring in as many (or more) than they trap. Squashing them one at a time is gross *crunch* and time-consuming. The New York Times had an article once upon a time that claimed mixing a handful (yuck) in a blender with some dishwasher soap, diluting the mess and spraying it on whatever is left of your garden was effective. Further Googling finds opposing viewpoints. I couldn't get past getting a second blender from St Vinnies plus a sprayer that wouldn't clog with beetle puree. The trap has it's own drawbacks. After a few days of beetle trapping, the bag starts to S T I N K . However, I have found that you don't need the custom bags they'll sell you. Simply find an appropriately sized plastic bag then make the bottle neck by lightly choking it off with a wire garrotte. (sp?)
The clumsy beetles, apparently drunk, are unable to climb back up the slippery plastic side of almost any plastic bag. I used a Sentry Foods bag. The harder, shinier plastic and the 'elderly' sized bag seemed to do the trick. Then I dumped the 2-3 cups of beetles into a bucket with a little bleach and flushed the whole mess. Yuck
The beetles seem worse this year than last and are making lace out of everything from sweet potato vine to the echinacea. Bastards.

Last year I saw a few on the Near East Side for the first time. This year there are hundreds if not thousands in my yard. I don't think they've made it to the West side yet, at least not where I have friends.

They definitely have, though I think they were a bit worse last year... and (cross fingers) seem to be on the wane.

We go the labor-intensive route of going out a couple times a day with a pan of soapy water and knocking them into it (they tend to drop when disturbed rather than fly, though that is not always the case).

After venturing over to the East Side for a dose of Olbrich Gardens...I was astonished that I only found ONE (1) Japanese Beetle in the whole place. A sign claims they pick them off 'by hand'. My guess is they spray the dickens out of them 'by hand'. An aside: Stopped by Burrito Drive after...nothing special happening there. $20 worth of tacos should make it hard to walk.

At any rate, safely back on the West Side, the beetle bag is bulging and there is no way in hell I am going to pick them off 'by hand', foot or any other appendage. If only there were a beetle repellant as effective as fox pee is for bunnies.

May a Green Bay gardener be invited to this site? I am grieving over my grape vine AGAIN, and apple trees and newly planted cherry tree.

I have been battling these beetles for a few years now. And YES, it is very much like a plague here also. A few years ago my neighbor observed a skunk in my yard digging for food - grubs to be exact. Also, I had numerous robins - they also enjoy grubs. Then I noticed my grass was dying. Grubs. Little did I know that these are all symptoms of JAPANESE Beetles!

I did the bag trick the year before my adorable skunk arrived on the scene - confirming that this method attracts more beetles and that year laid the "groundwork" for a greater population the following year. DON'T do the bag! PLEASE - DO NOT DO THE BAG!

I then did the pick off/squish method/add to soapy water and leave to stink up my beautiful grape vine area - gross!

I then did the baby shampoo trick - better - not effective - then this year I sprayed with some awful stinky poison - not enjoyable, and the beetles seem to land anywhere I was not able to spray.

NOW, I am using a combination of garlic powder, dish soap and vegetable oil. This seems to do the trick, and I do not mind respraying this concoction over and over again as I know it will not create health issues for myself. The beetles seem to scram as soon as they smell the garlic!

One thing I did not do this year due to the late spring was to plant marigolds....as I did last year and had better success with keeping the beetles away.

One year I hung out three Japanese beetle traps and each sagged under the weight of the trapped and dead beetles. Problem is, I had as many on my flowers and beans as in the traps. This summer, no traps and only a few beetles.

I've read that a small hand-held vacuum works well to suck up the bugs without having to touch them or spray anything. Haven't tried it yet. I had them terribly in De Forest when I gardened there, up until this year; no garden this summer, due to moving. They especially loved to devour hollyhocks, and seemed to like to hang out in bunches on the raspberries. I've done the 'tapping them into a bucket of soapy water' thing. It works, but it's very time consuming.